Chain-slack control.



c. FI YOCUM.

CHAIN SLACK CONTROL.

APPLICATlON FILEDWIAYIM Wlfq.

1,172,419. T rlatented Feb. 22,1916.

UNITED STATES PATENT OFFICE.

I CHARLES F. YOCUM, OF FINDLAY, OHIO, ASSIGNOB TO THE BUCKEYE TRACTION DITOHEB COMPANY, OF FINDLAY, OHIO, A. COBPOBATION'OF OHIO.

cnam-snacrcofiirnon 7 Specification. of Letters Patent. 7

Patented Feb. 22, 1916.

T 0 all whom it may concern:

Be it known that 1, CHARLES F. YOCUM, a citizen of the United States, and a resident of Findla in the county of Hancock and State of bio, have invented'a certain new and useful Chain-Slack Control; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the characters of reference marked thereon, which form apart of this specification.

My invention relates articularly to a chain controlling device or use in connection with the cutter driving mechanisms of excavating machines of the rotary cutter type, and has for its vobject to provide means which will automatically permit a lengthening out or taking up of slack in the cutter driving chain when the cutter is lowered or raised relative to the tractor frame, thereby preventing the necessity of removing or placing links 1n the cutter driving chain during such adjustments of the cutter wheel, as has heretofore been the case when making such adjustments. I

The invention is fully described in the following specification, and while, in its broader shown.

aspect, it is capable of embodiment in numerous forms, a preferred embodiment thereof is illustrated inthe accompanying drawings, in which,-

Figure 1 isa side elevation of a portion of a ditching machine embodying my invention, with the cutting wheel frame shown'in full lines at its maximum height and'in dotted lines at its maximum depth of cut, and.

Fig. 2 is an end elevation thereof looking toward the left in Fig. 1 and with parts removed.

Referring to the drawings, 1 designates the customary tractor frame, which may be of any suitable construction and mounted on a set of wheels 2, a portion of which are Rising from the rear end of the tractor frame 1 is a guide frame 3 with which the inner end of the cutting 'wheel frame 4 has vertical sliding connection, as indicated at 5. These features are well understood in the art and therefore need not be specifically described. The raising and lowering. movements of the cutting-wheel well understood in the art.

wheels 12 are connected by sprocket chains 15 with respective sprocket-wheels 16 on a shaft 17, which is journaledtransversely of the upright frame 3 in bearings 18 on the forward side thereofadjacent to the frame 1. The shaft 17 is preferably located approximately midway of the horizontal planes inwhich the shaft 11 stands when at the two extreme positions of vertical movements with the cutting-wheel frame, 4, as shown in Fig. l. The shaft17 also carries, in the present instance, a sprocket-wheel 19, which has connection through the medium of a sprocket-chain 20 with a suitable source of power as, for instance, a motor which is customarily mounted on the forward portion of the tractor frame.

' The portions of the two sprocket-chains 15, which connect the under sides of the respective sprocket wheels 12 and 16 are the active or working portions of the chains and are therefore held taut during a driving of the cutting wheel.

It is evident that inasmuch as the raising and lowering movements of the shaft 11,

carrying the sprocket-wheels 12 with the cutting-wheel frame 4, are in a plane which .is parallel to the frame guiding portion of portion of the chain 15 to vary quite a considerable extent. In order to prevent the slackened portion of the chain from-winding up on the inner portion of the sprocket wheel 16 which is turning in the directionindicated by the arrow, it has heretofore been the practice to remove links from the chain to compensate for such slackness and to then replace such links when the shafts 11. and 17 are receding from eachother during an adjusting of the cutting wheel frame.

The purpose of this invention is to obviate the necessity of removing links from and replacing them in the chain as the adjusting of-the guiding wheel frame takes place, and to provide means which automatically takes care of the slack in the chain as the adjustment of the cutting-wheel frame may require. To accomplish this a shaft 21 is mounted transversely of the cutting-wheel frame 4 in bearing standards 22 rising from respective sides of the frame 4: and between the shaft 11 and the upright guide frame 3. The shaft 21 carries an idler.sprocket-wheel 23 for the upper idler portion of each chain 15 to engage with over the top thereof, and is disposed at such a height above the horizontal plane of the shaft 11 that the under side of the idlersprockets 23 will not be lowered into contact with the top side of the lower working portion of the respective chains when the cutting-wheel frame has been lowered the maximum extent, as indicated by the dotted line position of the idler sprocket-Wheel and chain in Fig. 1. 7

It will be noted that when the cutting wheel frame is at its maximum lowered position the shafts 11, 17 and 21 approximately aline, the shaft 21, in the present instance, being slightly above a line drawn between the shafts 11 and 17. When the cutting wheel frame 4 is raised from the lowered dotted line position shown, the chain slackens to a maximum extent when the shafts 11 and 17 stand in a common horizontal plane, and as the shaft 11 moves above the horizontal plane of the shaft 17 the slackness in the chain is gradually taken up. During the entire adjustment of the cutting wheel frame 4, however, the slack portion of the chain is either taken up or let out by the action of the idler .procket 23 as the shafts 11 and 17 ap proach or recede from each other, thereby allowing for suihcient chain when the sprocket wheels 12 and 16 are spaced a maximum extent, and taking care of the slack in the chain when the sprocket wheels are spaced a minimum extent.

I Wish it understood that my invention is not limited to any specific construction, arrangement or form of the parts, except in so faras such limitations are specified in the claims.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is, i Y

1. In a machine of the class described, in

combination, a shaft, 3. sprocket-wheel carried by said shaft, a frame vertically adjustable With respect to said shaft, a second shaft carried by said frame, a sprocket-wheel carried by said second shaft, :1. sprocketchain connecting the sprocket-wheels on said first and second shafts, and an idler sprocket carried by said frame for supporting the upper idler portion of said chainand compensating for the varying difference in the distance between said shafts when said a frame is vertically adjusted.

'2. In a machine of the class described, an upright guide frame, a shaft which is sta-' tionary as against transverse movements with respect to said frame, a cutting-wheel frame guided for vertical movements by said guide frame, a cutting-Wheel driving shaft carried by said cutti-ngwvhecl frame. sprocket-wheels on both said shafts, a sprocket chain connecting said sprocket wheels, the under portion of said chainserving as the driving portion thereof, and an idler member carried by said cutting-wheel frame above the horizontal plane of the axis of the cutting-wheel driving shaft and supporting the idler portion of said chain intermediate the sprocket-wheels.

3. In a machine of the class described, in combination, a main frame, a cutting-wheel. frame carried by and vertically adjustable relative to said main frame, a shaft carried by each of said frames, sprocket wheels carried by said shafts, a sprocket chain connecting said wheels and having the lower portion thereof serving as the working portion, and an idler member carried by said adjustable frame and supporting the upper idler portion of said chain, said member being carried a predetermined extent above the horizontal plane of the sprocket-wheel which .is carried by the cutting-wheel frame shaft.

'-l. in a machine of the class (lescribed.in

through the axes of said shafts.

In testimony whereof, I have hereunto signed my name to this specification.

CHARLES F. YOCUM.

' axis disposed near a straight line drawn 

